1. Field of the Invention
This invention relates to a connector used in wiring of an automobile or the like.
2. Related Art
In a conventional connector of this type, when a metal terminal having a wire connected thereto is to be inserted into and retained on a connector housing, the metal terminal is retained by an elastic retaining piece formed on the connector housing, thereby preventing rearward withdrawal of the metal terminal. A retainer attached to the connector housing prevents an accidental movement of the elastic retaining piece, so that the metal terminal can be held stably.
Namely, the retainer engages the elastic retaining piece to limit the movement of this elastic retaining piece. There is also known a connector of the type in which projections formed on a retainer are engaged with retaining projections formed at a retainer fitting portion in such a manner that the retainer is retained provisionally and completely.
For example, a conventional retainer 104 shown in FIG. 11 includes relatively short lock arms 110b each having a completely-retaining projection 111b, and relatively long lock arms 110a each having an extension portion 113 and a provisionally-retaining projection 111a. A prevention piece 112a is provided between the adjacent short and long lock arms.
Another conventional example of a similar construction shown in FIGS. 12 to 14 is disclosed in Japanese Utility Model Unexamined Publication No. 4-24271.
FIG. 12 is a perspective view of a connector retainer 104 used in a conventional relay block housing, FIG. 13 is a cross-sectional view showing a condition in which the retainer 104 is provisionally retained on the housing 101, and FIG. 14 is a cross-sectional view showing a condition in which the retainer 104 is completely retained on the housing 101.
This retainer 104 includes a prevention piece 112a for limiting the movement of an elastic retaining piece 107a, and a relatively short lock arm 110b having a projection 111b, and a relatively long lock arm 110a having an extension portion 113 and a projection 111a, these lock arms serving to retain the retainer on the housing 101 provisionally and completely.
When the retainer 104 is to be provisionally retained, the projection 111b of the lock arm 110b engages an upper surface of a projection 109b on an inner wall 105b whereas the projection 111a of the other lock arm 110a engages a lower surface of a projection 109a on an inner wall 105a, thereby provisionally retaining the retainer 104, as shown in FIG. 13.
When the retainer 104 is to be completely retained, the projection 111b of the lock arm 110b engages a lower surface of the projection 109b of the inner wall 105b, thereby completely retaining the retainer 104, as shown in FIG. 14.
Here, even if the retainer 104, inverted in a right-left direction, can be attached to the housing 101, the projections 109a and 109b, as well as the projections 111a and 111b, are disposed asymmetrically, and therefore the retainer will not function properly.
In each of the above conventional constructions, the conventional retainer has the lock arms of different lengths which are used as the retaining portions for provisional and complete retaining purposes, respectively. Namely, the retainer is engaged by the lock arms separate from the elastic retaining piece for retaining a metal terminal, and the lock arms are asymmetrical right and left.
Because of this right-left asymmetrical arrangement, in a step of attaching the retainer to the connector housing particularly in the former conventional example, the retainer has often been inserted into the housing in a reverse manner, thus inviting a problem that the efficiency of the operation has been low.
Particularly in the latter conventional example, the retainer can not be of a small size because of its complicated construction, and therefore there has been encountered a problem that a mold is costly.
Furthermore, in either of the conventional examples, the prevention piece for limiting the movement of the elastic retaining piece is interposed between the lock arms through narrow slits, and therefore it has been difficult to withdraw an erroneously-attached metal terminal. Namely, for effecting such a terminal withdrawing operation, a terminal withdrawing jig is inserted into the connector housing through the slit from the retainer side after the retainer is brought into the provisionally-retained position, and then the elastic retaining piece is elastically deformed by it. However, when the jig is inserted, the prevention piece becomes obstructive, so that it has been difficult to elastically deform the elastic retaining piece. If the jig is forcibly inserted, the connector housing or other portion is gouged.